Tracking Price Changes

Is there a thread tracking the changes in costs of Model S ownership. I would want to know base price changes, specific option price changes as well as changes in the cost of various service plans. I know the options are particularly tricky as some are new and others have been tied or untied to other options, but it still would be interesting to see how all these prices are changing. It seems to me that price changes used to be explained in TM blog posts, but are now changed without notice in at least regards the options.